<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="./css/style.css">
    <style>
        .container {
            width: 500px;
            height: 300px;
            grid-template-columns: 1fr 1fr;
            grid-template-rows: 1fr 1fr;
            border: 2px solid #333;
        }
    </style>
    <script src="./demo.js"></script>
</head>
<body>
    <br>
    <p>
        <label for=""><input type="radio" name="option" value="stretch" data-attr="alignItems">stretch</label>
        <label for=""><input type="radio" name="option" value="start" data-attr="alignItems">start</label>
        <label for=""><input type="radio" name="option" value="end" data-attr="alignItems">end</label>
        <label for=""><input type="radio" name="option" value="center" data-attr="alignItems">center</label>
    </p>
    <br>
    <div class="container">
        <div class="item">1</div>
        <div class="item">2</div>
        <div class="item">3</div>
        <div class="item">4</div>
    </div>
</body>
</html>